2012 Final FWCP Seton Corridor REPORT
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Seton River Corridor Corridor REPORT 2012 9 1. INTRODUCTION 1.1!Proponent Information Cayoose Creek Indian Band - Sekʼwelʼwas - are the beneficiaries of large traditional sustenance gathering areas, that are and should be managed in a holistic relationship with the flora and fauna communities. We are located in the southern-interior of BC in close proximity to Lillooet within Stʼatʼimc territory. Our membership consists of approximately 200 registered members with 100 living on reserve. We have 720.1 hectares of reserve lands broken into three areas. It is the Mandate of Chief and Council to assist us in exercising our Title and our Right to manage our lands as in the past. We seek to work in an environmentally sensitive way on our traditional lands, using both cultural and scientific knowledge. We have spent the past seven years working in partnership with the Lillooet Naturalist Society on a restoration project at the confluence of the Seton and Fraser Rivers, and have undertaken survey work in the Seton River Corridor over the last three years. 1.2!Hydroelectric Impact In the late 1950s the Seton watershed was subject to major alterations from hydroelectric development. The Seton Corridor relates directly to the historical loss of habitat due to construction of the BC Hydro Bridge River hydroelectric facilities. The Seton hydroelectric development is just one component of the larger Bridge River system. The Bridge/Seton development resulted in creation of Carpenter Lake Reservoir behind Terzaghi Dam, which diverts water, through the mountain, from the Bridge River watershed into Seton Lake. The Seton portion of the project, in service since 1956, consists of Seton Dam just below the outlet of Seton Lake, where the majority of water is diverted into a 3.7km long concrete lined power canal. Water then flows through the powerhouse out into the Fraser River (Map 1). Some of the footprint impacts indicated in the BCRP Strategic Plan 2000 include: • Diversion of colder, nutrient poor Bridge River water to Seton Lake has changed the temperature regime and nutrient productivity of Seton Lake/River. • Dredging to construct the approach channel to Seton Dam removed riparian habitat, upland forested hillsides and caused the loss of significant spawning habitat for pink salmon - spawning channels were built to compensate this loss. • Construction of the project facilities reshaped the channel and banks, removed aggregates, and removed riparian vegetation over an extensive distance below the dam and at the confluence of Cayoosh Creek. • Diversion of water from Bridge River and Cayoosh Creek has effects on wetted channel area, seasonal temperatures and stream productivity. • Olfactory cues for sockeye returning to Gates and Portage creeks have been changed based on proportion of Cayoosh water mixed in tailrace discharge. • Fish migration impeded by powerhouse penstock, spawning channels and Seton Dam. • Dam traps gravel bedload and high flows erode original spawning gravels below the dam, decreasing spawning habitat. • Dam traps woody debris normally recruited downstream. • Lower water levels reduce fish access to former off channel habitat • Construction of the dam and canal have caused wildlife barriers which restrict movement within the corridor - thereby reducing available habitat and fragmenting populations. • Loss of significant wetlands at the confluence of the Seton and Fraser Rivers. • Visual impacts and invasive weed dispersal along hydroelectric powerlines. Seton River Corridor Corridor REPORT 2012 10 The development that has taken place along the Seton River Corridor is extensive. Historical photograph (Fig 1) shows an aboriginal fish camp (Oleman family) at Skimka (todayʼs Seton Beach) “in the days when salmon were thick” (BC Archives). Today, no fish are dried here. Map 1 Seton Hydro Project Facilities (map from BCRP, Strategic Plan - Volume 2) Fig 1 Oleman family fish camp and drying racks at Skimka.